1. Technical Field
The present invention relates to a radiation image detection apparatus and a radiation image photographing system.
2. Related Art
An X-ray image photographing has been widely distributed in areas such as, for example, medical diagnoses and a non-destructive inspection. In a general X-ray image photographing, an X-ray is irradiated to a subject and attenuated while transmitting through each part of the subject. The transmitted X-ray is then detected and an X-ray image of the subject is acquired based on the intensity distribution of the transmitted X-ray.
Recently, as for a medium for detecting an X-ray, a flat panel detector (FPD) having a two-dimensional array of pixels for detecting an X-ray has been used to convert the detected X-ray into an electrical charge signal and generate a pixel data based on the charge signal output from the pixel array.
In general, various correction processes are performed on image data of a subject acquired by the FPD to present an image based on the corrected image data as the X-ray image of the subject. An example of the correction process may include an offset correction.
The offset correction removes a dark current noise of each pixel of the FPD, and the dark current is measured as an electrical signal output from each pixel while the X-ray is not irradiated to each pixel. The offset correction removes the dark current noise that is different in each pixel by subtracting the dark image data generated while the X-ray is not irradiated to the pixels from the image data generated while the X-ray is irradiated to the pixels. Dark image data is acquired in a series of photographing sequences of acquiring the X-ray image data, and for example, acquired after the X-ray image data is acquired.
In the X-ray image photographing, so called an electronic cassette configured such that the FPD is accommodated in a portable housing is widely used and the image data acquired by the electronic cassette is transmitted through a wire communication or wireless communication to a console in which the operations such as a photographing condition setting or a photographing command are conducted, and the image is displayed in the console.
Further, when the photographing result is con firmed early so that, for example, the necessity of rephotographing can be determined quickly, it is possible to smoothly perform a workflow in a diagnosis or a check-up. From this standpoint, an X-ray image photographing system has been proposed in which a reduced image data is generated from the X-ray image data, the reduced image data is transmitted to the console prior to transmitting the X-ray image data or the dark image data, and the preview image is displayed in the console (see, for example, Patent Document 1 (JP-A-2006-026083)).